In 3d asymptotically flat bulk and two dimensional boundary theory, progress has been somewhat better. The symmetry group in question is BMS\(_3\) . Following the assertion that the putative dual theory has to be a BMS-invariant 2d field theory in [1]}, [2]}, a body of work has emerged, a selected, non-exhaustive list of which includes [3]}–[4]}. The study of 2d BMS invariant field theories is thus important to building on this proposed correspondence.
